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The Lower Permian Vrchlabí Formation was deposited in the Krkonoše Piedmont Basin of the Czech Republic during theAutunian (297–299 Ma) when global climate was characterized by a prolonged cold phase of the Late Paleozoic Ice Ageand when terrestrial environments shifted toward more arid conditions as atmospheric pCO 2 decreased. The RudníkHorizon of the lower Vrchlabí Formation is a well studied interval that records extensive lacustrine deposition. However thefine-grained redbed interval that underlie this interval are less well studied. In order to contrast the geochemistry of theseredbed arid climate facies with the deposits formed during inundation by the Rudník lacustrine system, we analyzed 17 fine-grained samples of varying lithology using XRF and LOI analysis from a detailed section through ~100m outcrop exposureof red beds near the down of Vrchlabí. These samples represent 5 different facies: 1) featureless maroon reddishmudstone, 2) pedogenic red-brown-orange mudstone, 3) gray laminated shale, 4) pedogenic gray mudstone and 5) yellowlaminated siltstone. Facies 5 produced substantially different results from the others, having the highest LOI (~21%)compared to 8.8-12.3% for all other facies, and lower Al overall than the other facies (13% compared to 18-20%). Facies 5is interpreted to represent a paludal mudstone that experienced calcite precipitation during deposition. Chemical Index ofAlteration (CIA) was highest for Facies 1 (70.1) and this facie also exhibited the highest Ti/Al (0.04) and is consistent withhighly weathered sediment influx and could represent a loessite. Facies 3 and 4 show similar average CIA values (63 and69, respectively); this is interpreted to indicate that Facies 3 formed from less chemically weathered sediment that servedas the parent material which was then subject to weak pedogenesis to form Facies 4. In contrast, Facies 2 showed muchlower average CIA value (57). This is interpreted to suggest pedogenic carbonate was precipitated, which also would havecaused the overall higher Ca/Al (0.38) for Facies 2 compared to the other facies, including the red beds of Facies 1 (0.09).Altogether these results suggest variable sediment influx under variable environmental conditions prior to the developmentof the Rudník lacustrine system. 

Transportation infrastructure experiences distress due to aging, overuse, and climate changes. To reduce maintenance costs and labor, researchers have developed various structural health monitoring systems. However, the existing systems are designed for short-term monitoring and do not quantify structural parameters. A long-term monitoring system that quantifies structural parameters is needed to improve the quality of monitoring. In this work, a novel Transportation Rf-bAsed Monitoring (TRAM) system is proposed. TRAM is a multi-parameter monitoring system that relies on embeddable backscatter-based, batteryless, and radio-frequency sensors. The system can monitor structural parameters with 3D spatial and temporal information. Laboratory experiments were conducted on a 1D scale to evaluate and examine the sensitivity and reliability of the monitored structural parameters, which are displacement and water content. In contrast to other existing methods, TRAM correlates phase change to the change in concerned parameters, enabling long-term monitoring. 

Radio frequency identification (RFID) is a technology for automated identification of objects and people. RFID technology is expected to find extensive use in applications related to the Internet of Things, and in particular applications of Internet of Battlefield Things. Of particular interest are passive RFID tags due to a number of their salient advantages. Such tags, lacking energy sources of their own, use backscattering of the power of an RF source (a reader) to communicate. Recently, passive RFID tag-to-tag (T2T) communication has been demonstrated, via which tags can directly communicate with each other and share information. This opens the possibility of building a Network of Tags (NeTa), in which the passive tags communicate among themselves to perform data processing functions. Among possible applications of NeTa are monitoring services in hard-to-reach locations. As an essential step toward implementation of NeTa, we consider a novel multi-hop network architecture; in particular, with the proposed novel turbo backscattering operation, inter-tag distances can be significantly increased. Due to the interference among tags’ transmissions, one of the main technical challenges of implementing such the NeTa architecture is the routing protocol design. In this paper, we introduce a design of a routing protocol, which is based on a solution of a non-linear binary optimization problem. We study the performance of the proposed protocol and investigate impacts of several network factors, such as the tag density and the transmit power of the reader.